Program Director/Principal Investigator (Last, First, Middle): Gantz, Bruce J. PROJECT SUMMARY ? PROJECT 1 The past 35 years of cochlear implant (CI) research have focused on outcomes primarily related to speech perception. Candidacy recently has extended into the less severely impaired population due to newer, shorter implants, including hybrid (acoustic-plus-electric) designs. The potential for improvement/change in domains other than speech perception can inform both policy and rehabilitative decision-making. Human ecology describes the relationship between humans and their natural, social, and built environments. This concept considers that human behaviors must be studied from both the social and natural science vantage points. In hearing health care, success with intervention is as much related to the anatomy/physiology of the individual as it is to the environmental and personal (i.e., ecological) factors that make each individual unique from the next. The overall goal of this project is to determine the impact of intervention on user's hearing-related functions and disability in their natural environments (i.e., real-world outcomes) and to clarify what ecological factors, as well as perceptual factors, affect these real-world outcomes. To date most cochlear implant (CI) research has focused on determining the effect of anatomical and physiological factors on laboratory outcomes, such as speech perception. We recognize, however, that the real-world outcomes exhibit great heterogeneity, which is likely due, in part, to the broader range of environmental and personal contextual (i.e., ecological) underpinnings in the hearing impaired population. As has been the case with hearing aids (HA), much variance can be accounted for by examining individual ecological factors. Very little is understood about (1) the characteristics of ecological factors of the CI population, (2) the influence that ecological factors have on the heterogeneity of real-world outcomes of this population, and (3) how this influences changes over time. With the expanded indications for CI quantifying the ecological factors that parlay into real-world outcomes in CI is critical because real-world outcomes ultimately determine societal burden and policy. Furthermore, because traditional retrospective self-reported outcome measures are often subject to recall bias, we will, in addition to standardized questionnaires and a data-logging feature on the processors, use a smartphone-based ecological momentary assessment (EMA) system to capture users' real-time experiences in situ (i.e., in natural environment). This will allow for measurement of the characteristics of listening environments in addition to subjective assessment of listening difficulty/ease. Two Aims have been designed to study the influence of ecological factors have on outcomes of listeners with a CI. Aim 1. To characterize environmental factors that are relevant to listening and communication for participants in each intervention group (Aim 1A) and to determine the effect of intervention on these factors (Aim 1B). Aim 2. To document the effect of intervention on real-world outcomes (Aim 2A) and determine to what extent environmental, personal, and perceptual factors moderate those outcomes (Aim 2B) over time (Aim 2C).